SQL Select only rows where exact multiple relationships exist

Question

This is closely related to this question, but adds another requirement.

Given a parent table \'parent\'

╔════════════╦════════╗
║ PARENT_ID  ║ NAME           


        

Answer 1

If you want to select all parents with at least a 5 and a 1, you can use:

SELECT PARENT_ID
FROM rel
GROUP BY PARENT_ID
HAVING SUM(PROP_ID = 1)
       AND SUM(PROP_ID = 5)
       AND SUM(PROP_ID NOT IN (5,1)) = 0

If you need exactly one 5 and one 1, see this answer